What is a Colon?

When I was first diagnosed with Ulcerative Colitis, I’ll be honest, I wasn’t 100% sure what a colon was, where it was located or it’s function. I knew that a colonoscopy involved having a camera stuck up your bum, but that’s about it. Over the last four years I’ve learned more about human anatomy and bodily functions than I care to know, but I wanted to know exactly what is up with my body. The more you understand, the better you’re able to tell the doctor what is going on.

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So, I figure I am not alone. I’m sure there are a lot of people that don’t know much about their colons. You don’t really have to think about them much until something goes wrong. Here is what I’ve learned in my research (Also, I’m not a doctor, so take everything I say with a grain of salt. For more information, see my disclaimer).

Let’s start with the basics. What is a colon? The main function of the colon is to absorb water, salt and other nutrients in the final stages of digestion. Waste material enters the colon from the ileum (small intestine) and makes it’s way through the colon down to the rectum and anus where it is finally pushed out of the body.

Because the colon’s main functions are to absorb water and salt, people who do not have a colon (such as ostomates or j-pouchers), are prone to dehydration and sodium deficiency.

The colon, or large intestine, is divided into four sections: the ascending colon, the transverse colon, the descending colon and the sigmoid colon.

The cecum, which is at the beginning of the colon where the colic valve is located is connected to the ileum. It receives the chyme (digested food) from the small intestine.

The ascending colon, which begins at the cecum, travels upward opposite of the colic valve. If you’ll remember from my digestion post, food, at this point has become nothing but water, plant fiber, electrolytes and even some dead skin cells! Once food reaches the colon, it is no longer being broken down.

From the ascending colon, near the liver, it bends abruptly to the left and becomes the traverse portion of the colon. This abrupt bend is what is known as the right colic flexure. It travels across the abdomen toward the descending colon where it takes an abrupt downward turn. This turn is known as the left colic flexure.

This downward turn into the descending colon is located just below the spleen. As it travels downward, it then reaches the sigmoid colon.

The sigmoid colon dips down and then has a slight upturn before meeting the rectum. It is surrounded by peritoneum, which support the abdominal organs and serves as blood and lymph vessels as well as nerves.

Well, there you have it, everything I know about colons. Also, if you get a chance, I would love for you to take my poll about Health Insurance. This poll was created with Dr. Peter Higgins. We are using the data gathered to help future IBD patients get the coverage they need for medications and treatments. You can take the poll by clicking HERE. Thank you for your time.

Sources:
Ten Facts About Your Colon
WebMD
Bowel Cancer Australia
MayoClinic
Guinness World Records
Crohn’s & Colitis Foundation of America
Inflamed & Untamed
Medicine.Net
News Medical
Medical Dictionary
Colon Cancer Alliance
Medline Plus